LED bulbs are light sources that use semiconductor materials rather than filaments to emit light. LED bulbs are generally more efficient light sources than incandescent light bulbs because LED bulbs are nearly monochromatic and emit light within a very narrow range of wavelengths. LED bulbs also generally last many times longer than incandescent light bulbs.
Light posts can be fitted with light sources to illuminate a street, parking lot, walkway, etc. Historically, incandescent lights with filament type bulbs have been used for illumination. Since incandescent light bulbs illuminate radially outward, the illumination is distributed approximately uniformly in all directions.